WEDNESDAY, AUGUST 7, 1985
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SLUDGE DISPOSAL PLANS IN THE PIPELINE
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COMPREHENSIVE PLANS FOR THE DISPOSAL OF ALL SLUDGES WERE BEING DRAWN UP SO THAT SLUDGE MANAGEMENT COULD FORM AN INTEGRAL PART OF HONG KONG'S WASTE DISPOSAL STRATEGY, SECRETARY FOR HEALTH AND WELFARE, THE HON CHAU TAK-HAY, SAID TODAY (WEDNESDAY).
IN REPLY TO A QUESTION BY THE HON ANDREW SO ON MEASURES BEING TAKEN TO TACKLE POLLUTION CAUSED BY SLUDGE DISCHARGED FROM WATER TREATMENT PLANTS, MR CHAU POINTED OUT THAT IN ADDITION TO THESE PLANS ON A BROADER FRONT, THE GOVERNMENT WAS ACTIVELY PLANNING ALTERNATIVE SCHEMES FOR SLUDGES PRODUCED BY FIVE OF THE 15 GOVERNMENT-OPERATED PLANTS.
+THE SLUDGE - KNOWN PROPERLY AS ALUM SLUDGE CONTAINS A HIGH LEVEL OF SUSPENDED SOLIDS AS WELL AS ELEMENTS, SUCH AS ALUMINIUM, WHICH ARE POTENTIALLY TOXIC, MR CHAU SAID.
HOWEVER, HE EMPHASISED THAT WATER QUALITY MONITORING HAD NOT INDICATED CONCENTRATION LEVELS REACHING ANYWHERE NEAR THOSE WHICH WOULD REPRESENT A DIRECT OR INDIRECT THREAT TO PEOPLE.
THESE SLUDGES ALSO CONTRIBUTED TO A REDUCTION IN THE AMOUNT OF OXYGEN IN RIVERS AND THE MARINE RECEIVING WATERS, HE ADDED.
REGARDING THE POINT ABOUT THE EXTENT OF POLLUTION AT SHING MUN RIVER CAUSED BY SUCH SLUDGE DISCHARGES, MR CHAU SAID ABOUT THREE QUARTERS OF ALL THE SLUDGE PRODUCED AT THE FIVE TREATMENT PLANTS AROSE AT SHA TIN WHERE IT WAS DISCHARGED INTO THE UPPER SHING MUN RIVER.
→WITHOUT ATTEMPTING TO MINIMISE THE SIGNIFICANCE OF THE SLUDGE PRODUCED AT SHA TIN, I WOULD POINT OUT THAT IT ACCOUNTS FOR ABOUT 10 TO 15 PER CENT OF THE TOTAL POLLUTION LOAD, MEASURED IN TERMS OF OXYGEN DEMAND, ON THE SHING MUN RIVER.
+THIS, TOGETHER WITH THE SLUDGE FROM A PLANT AT TAI PO, REPRESENTS ABOUT FOUR PER CENT OF THE OVERALL DAILY POLLUTIÓN LOAD ON TOLO HARBOUR, HE SAID,
THE ALTERNATIVE DISPOSAL SCHEMES UNDER ACTIVE PLANNING STARTED WITH THE PLANT AT SHA TIN.
*THE MAIN OPTIONS WHICH ARE BEING CONSIDERED ARE:
(A) DIRECT DISCHARGE THROUGH THE SEWERAGE SYSTEM TO
SEWAGE TREATMENT PLANTS, OR
(B) DEWATERING AND THICKENING OF THE SLUDGE PRIOR TO DISPOSAL, MR CHAU DISCLOSED, ADDING THAT WITHIN THE SECOND OPTION, THE GOVERNMENT WOULD ALSO NEED TO CONSIDER WHETHER THE TREATED SLUDGE SHOULD BE DUMPED AT SEA OR IN CONTROLLED TIPS,
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